// 保存字节

                        using (FileStream fs = new FileStream(Path.Combine(path, fileName), FileMode.Create))

                        {                        

                            while (uploadInfo.UploadedLength < uploadInfo.ContentLength)

                            {

                               //从输入流放进缓冲区

                                int bytes = this.fileUpload.PostedFile.InputStream.Read(buffer, 0, bufferSize);

                                // 字节写入文件流

                                fs.Write(buffer, 0, bytes);

                                //  更新大小

                                uploadInfo.UploadedLength += bytes;

                                //  线程睡眠 上传就更慢 这样就可以看到进度条了

                                System.Threading.Thread.Sleep(100);

                            }

                        }